Rotary well drill



Jan. 25,1927.

J. T. PHIPPS ROTARY WELL DRILL I Filed Feb. 18, 926

2 Sheets-Sheet 1 JTTQPMK 78 22 mum m Ja z Jan. 25,1927. T. PHIPPS FiledFeb. 18, 1926 [MA/7UP: J5 7' mes, X r 'ZT2'o2AJz'r Patented Jan. 25,1927.-

J'OHN TI PHIPPS, 01 LOS ANGELES, CALIFORNIA.

ROTARY wnrir. DRILL.

Application filed February 18, 1926. Serial No. 89,044.

This invention relates torotary Well drills and is particularly directedto drills of the character adapted for use in conjunction with thecirculating fluid system of well drilling.

In the usual rotary drilling system, the

drill is attached to the lower end ofa string of drill pipe which isrotated by a rotary table at the well surface and fed downwardly withthe progress of the drill, and mudladen fluid is pumped down the hollowdrill pipe to be discharged through circulation passages in the drill,said mud laden fluid flushing the drill and transporting the drill ingdetritus upwardly between the drill pipe and the wall of the well boreand to the surface where it flowsinto a settlingsump and is availablefor recirculation. The mudladen fluid further serves the very usefulpurpose of mudding up the wall of the well bore and preventing caving inof the formation.

In many types of rotary drills, and particularly in the ordinary type offish-tail hit, the circulation passages discharge the circulation fluidat points spaced a considerable distance from the cutting edges and thebottom of the well bore, and consequently when drilling in soft stickyformation there is a great tendency for the drill to mud-up, that is,the sticky mud is very liable to adhere to and pack solidly on thatportion of the drill below the effective flushing action of the streamsof fluid discharging from the circulation passages of the drill, withthe result that the drill is unable to make progress and may even becomefroze in the well bore. This is-due to the fact that even when the fluidis discharged from' the circulation passages of the drill underconsiderable pressure, into the body of fluid in the well bore, theflushing velocity of the fluid is dissipated within a .few inches of theoutlet of said passages and said fluid does not reach the bottom of thewell bore. As the outlets of said passages in many cases, especially inthe ordinary fish-tail drill, are

as much as two feet from the lower cutting edges of the drill, it willbe evident that the circulation reverses before reaching the bottom andconsequently the bottom of the bore contains fluid not subjected tocirculation or to ,flushing'. action. This dead fluid zone is the maincause of the mudding-up of ,ro-

tary drills.

In many instances this undesirable con-- dition has been partiallyovercome by carrying the circulation passages the entire length of thedrill body to discharge close to the bottom of the drill and while thisin some measure eliminates a portion of the trouble, the presentinvention has for an object to provide an improved arrangement ofcirculation passages in a rotary drill, by means of which mudding-up ofthe drill will be further if not entirely eliminated.

A further object is to incorporate such im proved arrangement ofcirculation passages in a drill of the fish-tail type.

Another object is to provide a fish-tail drill of the above character inwhich is included a replaceable cuttingblade.

Various other objects and advantages will be more fully apparent fromthe following description of the accompanying drawings which form a partof this disclosure, and which illustrate a' preferred form of embodiment of the invention.

Of the drawings:

d 1ig. 1 is a side elevation of my improved Fig. 2 isa bottom plan view.

Fig. 3 is a. vertical section of the drill body taken on line 33 of Fig.2, the detachahleblade and retaining pin having been removed.

Fig. 4 is a. vertical section on line 4-4 of Fig. 2. i

Fig. 5 is an enlarged plan section on line :5'--5 of Fig. 1.

perspective view of the detach- Fig. 6 is a able blade. 7 D

Fig. 7 is aside elevation of an integral fish-tail bit having theimproved circulation passage arrangement of t e present invention.

Fig. ,8 is an edge elevation of the bit shown in Fig. 7.

Fig. 9 is a vertical section on line 9-9 of F ig. v

Referring particularly to Figs. 1 to 6, 10 designates a one-piece drillbody of considerable length and of general cylindrical contour. havingdiametrically disposed win portions 11 which are of substantial width toprovide peripheral surfaces 12, of sufficient area to effectively serveas means for guiding the drill in a manner to produce a substantiallystraight well bore and also as a means for keeping the mud-laden fluidstirred up while the drill is rotating.

The upper end of the drill body is provided with the usualform ofscrew-threaded tapered pin-13 so that the drill may beat-- tached in theusual manner to the lower end of a string of drill pipe and the lowerend of the body is suitably rounded so as to offer the least possibleresistance to the flow of the circulation fluid.

The preferred ty e of detachable cutting blade comprises a ody portion14 having its lower end dressed in the wellknown fish-tail manner, and ashank 15 extending upwardly therefrom, said shank bein of less widththan the body portion and avthrough the body proper and said wings.

Continuing upwardly from said slot the body is recessed as at 19 toreceive the shank portion 15 of the detachable blade, said re.

cess bein of less width than the body and contourec in a mannercorresponding to the shape of said shank portion of the blade. (SeeFigs. 1 and 5.)

At 20 the body is transversely bored at an elevation to coincide withthe position of the groove 16 in the shank 15 of the blade when saidblade is in' place, the medial portion of the bore 20 intersecting therecess 19 to form the semi-circular groove 21 complementary to thegroove 16, saidgrooves cooperating to complete the circular holeaccommodating the retaining pin 17 As illustrated in Figs. 1 and 5, thebore 20 is shouldered, at 22 and has a terminal end 23 of reduceddiameter and the opposite wing 11*has a bore 24 having a tapped end toreceive a screw-thread ed locking pin 25.

In assemblingthe blade 14 into the drill body, it is inserted upwardlyin the slot 18 with its shank 15 disposed within the recess 19 and itsgroove 16 in regist with the groove 21 in the side wall of sai recess;and the bore 20. The retaining pin 17 is then inserted into the bore 20until it engages the shoulder 22, after which the locking pin 25 isscrewed into the bore 24 with its inner end extending across the bore 20to lock the retaining pin 17 in lace. When it is desired to removethebla e, and after the w locking pin 25 is first removed, the retainingclosing pin 17 may be driven out by a punch or other suitable instrumentinserted into the reduced terminal end 23 of the bore 20. v 7

Referring now more particularly to the circulation arrangement, it willbe observed that the body of the drill is provided with a central bore26 extending downwardly from,

the upper surface ofthe tapered pin 13. To facilitate manufacturing thiscentral bore in tersects the recess 19 although from the standpoint offunction this is not essential. The upper end of the bore 26communicates with the. interior of the string of drill pipe throughwhich the circulation fluid is pumped downwardly to the drill, andintersecting said bore 26 and slightly diverging downwardly are twocirculation passages 27 dischar ing downwardly at the lower end of thebody-respectively on opposite sides of the cutting blade 14. Itwill benoted that these circulation passages are disposed each to discharge itsflushin jet in front of the adjacent cutting edge of the blade.

This arrangement provides downward circulation discharging from thelower end of the drill closely adjacent the bottom of the well bore andeliminates any zone of noncirculating fluid which wouldtend to inducemudding-up of the drill.

Toeaccelerate the return circulation and the elevation of the drillingdetritus I provide additional circulation passages 28 discharging aportion of the circulation fluidupwardly along opposite sides of thedrill body, these passages 28 communicating at their lower ends with thecentral bore 26 through short transverse passages 29 formed by boringinto one side of the drill bod the outer end of said bore beingsubsequent y closed by a plug 30 welded or otherwise 'secured in place.

In Figs. 7 to 9, the circulation arrangement above described is shown asapplied to an integral fish-tail bit, in which the medial portion 31 ofthe blade is enlarged to cylindrical form and extends to within a shortdistance of the bottom or cutting edge of the blade. A central bore 26"extends downwardly from the upper surface of a tapered pin 13 andcommunicates with a transverse passage 29" formed'by boring into oneside of the body and subsequently the end of-said bore by a plug 30.Circu ation passages 27 extend downwardly from'said, usage 29' anddischarge upon opposite si es of the cutting blade, and returncirculation passages. 28 extend upwardly from said passage 29 anddischarge upwardly along opposite sidesof the body.

The improved arrangement of circulation passages or parts hereindescribed rovides downwardly directed flushing jets 'scharginglsufliciently close to the bottom of the e bore to insure quick elevationof all of the drilling detritus, and provides means vfor reversing aportionof the circulating fluid within the drill body and for directingflushing jets upwardly to accelerate the return circulation.

While the particular embodiment herein illustrated and described is welladapted to fulfill the objects primarily stated, it is to.

be understood that the scope of the invention is not limitedthereto,-for it is susceptible of embodiment in various other forms,-all coming within the scope of the following claims.

I claim as my invention:

1. Arotary drill compnsing a body having means at its upper end forattachment to.

a drill pipe and provided with cutters at its lower end, there being abore extending downwardly and terminating "insaid body and positioned toreceive circulation fluid from said drill pipe, said body being pro--vided with circulation passages for reversing the circulation within thebody and dis charging upwardly and exteriorly of the body and othercirculation passages extending to the lower end of the body anddischarging a portion of said fluid towards the cutters.

2. A rotary drill comprising a body having means at its upper end forattachment to a drill pipe and provided with cutters at its lower end,there being a central bore extending downwardly and terminating insaidbody and adapted to receive circulation fluid :from said drill pipe,said body being provided with circulation passages communicating withsaid central bore and positioned to .re-

verse. the circulation within the body and discharge u 'wardly andexteriorly of the body and ot er circulation passages communicating withsaid central bore and extending downwardly to the lower end of the bodywards the cutters.

3. A rotary fish-tail drill comprising: a body having a transversecutter blade extending below its lower end and provided with ascrew-threaded tapered pin at its ,lation fluid withint e body anddischarging a portion of said fluid toand circulation [passagescommunicatmg with said bore'and extending downwardly tothe lower end ofthe body anddischarg- I ing on opposite sides of said cutter blade, andother circulation passages communicat ing with said bore and extendinwithin the body and discharging said fluid upwardly along the exteriorofthe body. a

4. In a rotary fish-tail drill, the combination of: a body having meansat its upperend Ifor attachment to a drill'pipe and proextendingupwardly into the body," said body being provided with a recessextending upwardly able cutting blade positioned in said slot andextending below the body, having a shank extending into said recess andprovided with a transverse groove cut into one ofits side surfaces, thebody being provided with a transverse bore. registerin exlt endingthrough said bore. and said groove, said body .having'a bore extendingdownwardly and positioned to receive circulation fluid. from said drillpipe, there being a circulation bore. extendlng downwardly andterminating in said body and circulation passages in said bodycommunicating with said circulation bore and extending; downwardly .tothelower end of the body and discharging on opposite cutting blade, saidbod beingfurther pro vided with other circu ation' passages colmmunieating with'said bore and extending upwardly to reverse a portion ofthe circu and discharge said fluid upwardly along the exteriorof thebody.

with said groove; and a retaining pin.

upwardly ,to reverse a portion of the'circu ation fluid *vided atitslower end with a diametric slot I from the base of said slot;' adetachsaid; blade sides of said

